Saying the U.S. State Department’s advice on travel to Mexico “underplays” the risks to Americans who drink alcohol at resorts, a Massachusetts senator is calling on the agency to strengthen its warning.

In a letter to Secretary of State Rex Tillerson, U.S. Sen. Edward Markey (D-Mass.) said he is concerned “for the safety of U.S. citizens vacationing in Mexico who consume potentially tainted alcohol” and who might have a false sense of security at resorts.

Markey’s letter, sent on Thursday, follows one earlier this month from U.S. Sen. Ron Johnson (R.-Wis.), who urged the department to work with Mexican officials to get answers into what is behind a swelling number of tourists who report blacking out after drinking small and moderate amounts of alcohol at all-inclusive resorts.

The action comes in the wake of a Milwaukee Journal Sentinel investigation into the death of Conner — and a host of other injuries and deaths involving vacationers who blacked out after drinking at the resorts and woke up hours later.

Johnson, chair of the U.S. Senate Committee on Homeland Security and Governmental Affairs, asked for a response from Tillerson by Sept. 8.

On Tuesday, the state department updated its Mexico travel warning — as it does routinely every six months — to note an uptick in homicides and other drug-related violence around Cancun and other tourist regions.

“The Mexico Travel Warning issued on August 22, 2017, focuses solely on the risk of traveling to certain parts of Mexico due to the activities of criminal organizations and does not warn of the risks associated with the consumption of tainted alcohol,” Markey wrote to Tillerson.

A spokeswoman for Tillerson said Thursday the secretary “did not have any availability for an interview at this time.” Tillerson declined an earlier request for an interview by the Journal Sentinel as well.

Kevin Smith, a Hubertus resident, said he wished he had known about the dangers before he and his wife of 24 years booked a Mexican vacation for November.

"We had no idea any of this was going on," Smith said.

The Smiths canceled their trip and are in a dispute with their vacation rental company to have their money refunded.

"Our government should do something to protect our citizens," he said.

The information on the state department web page now cautions tourists who choose to drink alcohol to “do so in moderation and to stop and seek medical attention if you begin to feel ill.”

The Journal Sentinel has heard from more than 70 vacationers who experienced blackout problems while staying at the resorts, typically after drinking limited amounts of alcohol. In some cases, couples reported blacking out at the same time.

Those who sought medical care from on-site doctors or went to the hospital said they were met with demands for large sums of cash up front and that they were treated poorly. Those who attempted to report crimes, including sexual assaults, to police said resort officials discouraged them from doing so and that police themselves were reluctant to file reports.

State department officials have told the Journal Sentinel there is little they can do to help: U.S. officials can’t translate, offer legal advice or force Mexican resorts or hospitals to do anything to help U.S. citizens. And the agency does not keep data on how and where U.S. citizens are injured.

Mexican health authorities swept through 31 resorts, restaurants and bars in Cancun and Playa del Carmen following the Journal Sentinel reports and seized 10,000 gallons of illicit alcohol and shut down one of the bars — KuKulka in the Iberostar Paraiso Maya lobby — in the same resort complex where Conner drowned.

Authorities found "expired" and "unlabeled" alcohol at the bar, along with other sanitation violations.

Iberostar denied having “tainted” alcohol on its premises.

Read the investigation

For more on the Milwaukee Journal Sentinel investigation into alcohol-related blackouts at resorts in Mexico, or to tell us about your experience, go to jsonline.com/mexicoblackouts.